This invention relates to a high voltage power supply and, more particularly, to an adjustable high voltage power supply.
It is necessary in many applications to provide a regulated, high voltage power supply having a relatively high slew rate. This is particularly true in the field of mass spectrometry and related fields wherein high voltages typically in excess of 10,000 volts are varied, in order to sweep the ions and other particles being examined, down to voltages as low as 500 volts in short periods of time. These voltages must be accurate, stable, and have low noise.
Conventional couplings between the control voltage amplifier and the series pass tubes of a high voltage power supply have been found to be inadequate in that the operating characteristics of the high voltage tubes are such that it is extremely difficult if not impossible in most cases to obtain voltages much below 1500 volts with the retention of the low noise characteristics and the high slew rate for the power supply. If one is going to sacrifice the low noise criteria or if one is willing to sacrifice or settle for a slower slew rate of the power supply, conventional supplies often are adequate.
Accordingly, it is an object of this invention to provide an improved high voltage power supply having a high slew rate.
Another object of this invention is to provide an improved adjustable high voltage power supply which is relatively free from noise.